Project Abstract This K24 award will support the candidate?s development as a mentor and substance use researcher, while completing a study the impact of reduced or discontinued opioid therapy on patients infected with HIV. The candidate will complete advanced training in mentoring and meet regularly with senior mentors to improve his mentoring, while increasing his mentoring load throughout the award period. He will also enhance his ability to excel as a substance use researcher addressing opioid use and chronic pain by completing American Board of Addiction Medicine board certification and the American Pain Society Fundamentals of Pain Medicine course, completing independent structured reading programs addressing pain research as well as biostatistics and research design, and gaining direct clinical experience in chronic pain management. In addition, the candidate will pursue new research to examine the impact of discontinuation of prescription opioid use among HIV- positive patients. The candidate will perform extensive chart extraction research on 600 patients prescribed opioids for chronic pain (300 HIV-positive, 300 frequency-matched HIV-negative) in years 1-2 and 3-4 of the award period in order to characterize the trajectory of opioid prescribing and rationale for continuation or changes in opioid therapy, compare opioid prescribing patterns and yellow flag behaviors among HIV-positive and HIV-negative patients, and prospectively assess the relationship between receipt of prescription opioids and clinic care of HIV-positive and HIV-negative patients. Analysis will involve pooled logistic regression modeling adjusted for frequency-matching strata, and generalized estimating equations, depending on the hypothesis being tested.